The long-term goals of this research are to identify compounds that may be used in human trials to prevent and control eye melanoma metastasis. Despite advances in the treatment of primary ocular melanoma, there been no decrease in the mortality rate of this disease. In humans, ocular melanoma often spreads to the liver as micrometastases that have the potential to grow into vascularized metastases and lead to death. There is evidence that downregulation of the natural killer (NK) response is associated with an increase in micrometastases, and upregulation with immunotherapeutic agents such as interferon (IFN) decrease the number of micrometastases. Additionally, there is evidence that primary ocular melanoma produces angiostatin, an anti-angiogenic compound that suppresses growth of micrometastases into vascularized metastases. The objective of this proposal is to test the mechanisms of immunotherapeutic and anti-angiogenic/anti-melanoma invasion agents in a murine model of ocular melanoma that spreads to the liver and causes micrometastases that potentially grow into metastases. Intramuscular (IM) injections of IFN alpha-2b wil1 be given prior to enucleation and subcutaneous (SC) injections of angiostatin will be given just after enucleation of the eyes that contain melanoma. The IFN will eliminate micrometastases by enhancing the host NK response. Both the IFN and angiostatin will prevent the progression of micrometastases into metastases by anti-angiogenesis. Angiostatin will prevent metastases by an anti-melanoma invasion effect.